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EFFECT OF COAL UPGRADING ON RHEOLOGY OF COAL WATER MIXTURE DATIN F. UMAR; BUKIN DAULAY; HIROMOTO USUI; YOSHIYUKI KOMODA
Indonesian Mining Journal Vol 10, No 3 (2007): INDONESIAN MINING JOURNAL Vol. 10 No. 3 October 2007
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (231.871 KB) | DOI: 10.30556/imj.Vol10.No3.2007.609

Abstract

Coal water mixture (CWM) is coal-water slurry in which particles of coal with a certain particle size distribution are suspended in water. CWM is required to have the highest possible coal concentration and a moderate viscosity in order to make handling easy. The main purpose of this study is to obtain the effect of coal upgrading on the rheology of CWM in terms of finding the most suitable dispersing additive in producing CWM with highest coal concentration. Two kinds of coal, raw and upgraded coal, from three areas in Indonesia have been used. Three kinds dispersing additives, i.e. formalin conden- sation product of naphthalene sulfuric acid (NSF), polystyrene sulfonic acid (PSS) and poly (meth) acrylate (PMA) were tested to produce CWM with good flow characteristics. The rheology of CWM was prepared, measured by a stress control type rheometer (Rheometric Scientific Co. Ltd., SR-5) in steady shear mode at 25ºC. The apparent viscosity of upgraded coals showed a better slurry-ability of CWM as a function of coal concentration for every dispersing additive compared to the raw coal.
THE EFFECT OF DISPERSING AND STABILIZING ADDITIVE ON THE STABILITY OF UPGRADED COAL WATER MIXTURE DATIN F. UMAR; BUKIN DAULAY; HIROMOTO USUI; YOSHIYUKI KOMODA
Indonesian Mining Journal Vol 10, No 1 (2007): INDONESIAN MINING JOURNAL Vol. 10 No. 1 February 2007
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (301.495 KB) | DOI: 10.30556/imj.Vol10.No1.2007.629

Abstract

The upgraded brown coal water mixture (UBCWM) stability with several dispersing and stabilizing additives was studied based on coal sedimentation time history. UBCWM was filled up in a settling column; which has four holes in the upper, upper middle, bottom middle and middle side to take samples. Results indicate that the addition of Naphthalene sulfonate formaldehyde condensate (NSF) as dispersant together with S-194 some kinds of bio polysacharide with long branches produced by Dainippon Pharmaceutical Co. Ltd. as stabilizer, produces UBCWM with the best stability compare with that by using polystyrene sulfonate (PSS) and polymethacrylate (PMA) together with carboxyl methyl cellulose (CMC) and S-60 also some kinds of bio polysacharide, but without branches pro- duced by Dainippon Pharmaceutical Co. Ltd . Even the addition of S-194 results UBCWM with good stability, from the economical point of view, the addition of S-194 is a problem. The price of S-194 is expensive, whereas CMC is abundant and cheap. Therefore, the use of CMC as stabilizing additive was also effective in preparing stable UBCWM according to the stability of the UBCWM by using S- 194 and CMC is not significantly different.
EFFECT OF COAL UPGRADING ON RHEOLOGY OF COAL WATER MIXTURE DATIN F. UMAR; BUKIN DAULAY; HIROMOTO USUI; YOSHIYUKI KOMODA
Indonesian Mining Journal Vol 10 No 3 (2007): INDONESIAN MINING JOURNAL Vol. 10 No. 3 October 2007
Publisher : Balai Besar Pengujian Mineral dan Batubara tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30556/imj.Vol10.No3.2007.609

Abstract

Coal water mixture (CWM) is coal-water slurry in which particles of coal with a certain particle size distribution are suspended in water. CWM is required to have the highest possible coal concentration and a moderate viscosity in order to make handling easy. The main purpose of this study is to obtain the effect of coal upgrading on the rheology of CWM in terms of finding the most suitable dispersing additive in producing CWM with highest coal concentration. Two kinds of coal, raw and upgraded coal, from three areas in Indonesia have been used. Three kinds dispersing additives, i.e. formalin conden- sation product of naphthalene sulfuric acid (NSF), polystyrene sulfonic acid (PSS) and poly (meth) acrylate (PMA) were tested to produce CWM with good flow characteristics. The rheology of CWM was prepared, measured by a stress control type rheometer (Rheometric Scientific Co. Ltd., SR-5) in steady shear mode at 25ºC. The apparent viscosity of upgraded coals showed a better slurry-ability of CWM as a function of coal concentration for every dispersing additive compared to the raw coal.
THE EFFECT OF DISPERSING AND STABILIZING ADDITIVE ON THE STABILITY OF UPGRADED COAL WATER MIXTURE DATIN F. UMAR; BUKIN DAULAY; HIROMOTO USUI; YOSHIYUKI KOMODA
Indonesian Mining Journal Vol 10 No 1 (2007): INDONESIAN MINING JOURNAL Vol. 10 No. 1 February 2007
Publisher : Balai Besar Pengujian Mineral dan Batubara tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30556/imj.Vol10.No1.2007.629

Abstract

The upgraded brown coal water mixture (UBCWM) stability with several dispersing and stabilizing additives was studied based on coal sedimentation time history. UBCWM was filled up in a settling column; which has four holes in the upper, upper middle, bottom middle and middle side to take samples. Results indicate that the addition of Naphthalene sulfonate formaldehyde condensate (NSF) as dispersant together with S-194 some kinds of bio polysacharide with long branches produced by Dainippon Pharmaceutical Co. Ltd. as stabilizer, produces UBCWM with the best stability compare with that by using polystyrene sulfonate (PSS) and polymethacrylate (PMA) together with carboxyl methyl cellulose (CMC) and S-60 also some kinds of bio polysacharide, but without branches pro- duced by Dainippon Pharmaceutical Co. Ltd . Even the addition of S-194 results UBCWM with good stability, from the economical point of view, the addition of S-194 is a problem. The price of S-194 is expensive, whereas CMC is abundant and cheap. Therefore, the use of CMC as stabilizing additive was also effective in preparing stable UBCWM according to the stability of the UBCWM by using S- 194 and CMC is not significantly different.